There won’t be a single Congressman, Senator or governor on Tuesday’s ballot, but Wisconsin’s spring elections have attracted some of the nation’s most powerful political forces.

It is simply a race for a state Supreme Court judge — one of seven seats on the state’s high court — heading a ticket that will also decide a host of judgeships in counties such as Winnebago, Outagamie and Waupaca. But outside groups have poured millions into the top contest, the tea party movement has issued a call to arms, national labor unions have mobilized, and even Sarah Palin has weighed in.

“These spring elections in Wisconsin are usually sleepy affairs,” said Graeme Zielinski, state Democratic Party spokesman. “People are waking up.”

The awakening comes largely because of newly elected Gov. Scott Walker, a Republican who ignited what may be the most passionate union battle in a generation by pushing through a budget-balancing plan to end some collective bargaining rights for state workers. The battle has challenged organized labor’s might in state capitals across the country. And it has defined what will likely be a running national debate in the runup to the 2012 presidential contest.

“It’s because Scott Walker has stood with people like the Koch brothers in making Wisconsin a petri dish for these really extreme measures that don’t have any place here,” Zielinski said. “The fear is that if they can bust unions in Wisconsin, they can do it anywhere.”

Many believe that a win by the left-leaning challenger, state Department of Justice prosecutor Joanne Kloppenburg, over longtime Justice David Prosser would shift the balance of power in the state’s judicial branch, giving the left a 4-to-3 majority on the Supreme Court. That could play a prominent role in any effort to overturn Walker’s restrictions on collective bargaining. The winner will serve a 10-year term.

Indeed, the Tea Party Express, the conservative machine behind unlikely grass-roots Republican primary victories in Delaware and Alaska last fall, dubbed Tuesday’s Supreme Court contest “the most important election of the year.”

Although Walker is not on Tuesday’s ballot, the elections may be more about him than any of the 66 registered candidates.

“The battle in Wisconsin is far from over!” Tea Party Express leader Amy Kremer wrote to supporters Friday in a note supporting Prosser. “After the great work that Governor Walker did to help balance the budget, the liberal left is at it again! Big Labor is spending millions to help elect a liberal activist to the Wisconsin Supreme Court in their effort to overturn the fiscally responsible legislation that recently passed.”

In a testament to the local and national significance of the race, local television stations are already clogged with election-related independent expenditure advertising — reminiscent of a presidential contest.

“IEs rule the airwaves,” said Mark Jefferson, executive director of the state Republican Party, which, like its Democratic counterpart, is not allowed to make direct contributions to the candidates.

While outside spending in state races is sometimes difficult to track, roughly $1.7 million had been spent on the race through the middle of last week, according to a study produced by the Brennan Center for Justice at the New York University School of Law. The final total will be far higher.

The ads have turned nasty at times.

On Friday, the conservative group Citizens for a Strong America released a new ad responding to attacks from Kloppenburg allies claiming that Prosser allowed a child molester to go free. The new spot features one of the victims, Troy Merryfield, who says, “Now we’re being victimized again.”

“This time, Joanne Kloppenburg allies want to use our pain for their own gain,” Merryfield says. “I asked Joanne Kloppenburg to try to stop these false ads. Joanne Kloppenburg refused. It’s just wrong.”

The Tea Party Express this week vowed to buy “every available time slot on Wisconsin TV” to run its own advertisement, which attacks Prosser’s challenger, a repeat candidate. “Big union bosses want Joanne Kloppenburg, an activist judge they can control,” the ad says.

Jefferson said judicial elections are typically decided by qualifications and experience, but there’s no precedent for what’s happening this year.

“Whether or not the Walker thing overshadows all of the other issues, I’m not sure,” he said. “Wisconsin voters have tried to keep the partisanship out of the [Supreme Court] races. This time around, it’s inevitable there’s going to be some. The question is how much voters will tolerate.”

Palin may have raised the partisan stakes late last week.

In her usual style, the former Alaska governor and 2008 Republican vice presidential nominee tweeted her choice Friday.

“Wisconsin, please remember to vote for Justice Prosser on April 5,” Palin wrote in her endorsement, which was lauded by the Tea Party Express and received national attention.

Meanwhile, the nationalization of Wisconsin politics isn’t expected to end anytime soon.

Republicans and Democrats are pushing to recall state Senators involved in the collective bargaining fight.

Republicans, having made significant gains during the 2010 midterms, have the most to lose.

On Friday, local Democratic activists submitted the first batch of signatures needed to recall their eight targets. Assuming the state certifies the signatures, a special election to recall GOP state Sen. Dan Kapanke could be scheduled in mid-summer. And Democrats are on the way to forcing new elections in seven more districts held by Republican state Senators.

While Republicans may do the same in a handful of Democratic districts, a net Democratic pickup of three seats would shift control of the state Senate.

“Today’s news will send shock waves throughout Wisconsin, and it gives huge momentum to efforts in other Senate districts to gather recall signatures,” leaders of the liberal Progressive Change Campaign Committee wrote in a message to supporters Friday.

“Now’s the time to flood the Wisconsin airwaves with more of our TV ads supporting the recall and pump energy into places where volunteers are still working hard to gather signatures.”

The state party is leading a huge mobilization effort, according to spokesman Zielinski.

“You can’t throw a nickel, even in these small towns, without seeing a rally,” he said, adding that the state party may pursue a campaign to recall Walker himself. To be recalled, an officeholder must have one year of tenure, so Walker could face an effort in January.

Zielinski added: “This is the start to a long road back to sanity here in Wisconsin.”